The a/t oil hot light comes on my 1987 pathfinder automatic transmission 4w drive , what can it be ?

Seen 8 wires to radio, none orange. Are you looking for wire HOT AT ALL TIMES or HOT IN ACC OR RUN?

You will need the transmission replaced or revbuilt.

Whenever this warning light or any other stays on in the dash it is indicating that the systems control module (or the system sensor in the case of lights like low oil pressure, door open indicators etc.) has detected a fault, it then disables the system (this applies to ABS,TCS, TCM, SRS and BCM faults and others) as long as the light is on. You must now have the dealer hook up a special electronic diagnostic tool and "scan" the system for the fault code that is stored for the problem(s)

Legend of Abbreviations. ABS Antilock brake system.TCS Traction control system, TCM Transmission control module, SRS Supplemental restraint system, BCM Body control module

I would check the switch on the transmission which controls that circuit. It is called the backup light switch, or the neutral safety switch if it is an automatic.

ATP is Automatic Transmission Park Warning Light, means automatic transmission parking function is not engage.
You can try to shift the transfer control shift lever into the 2H, 4H or 4L position when the light comes on.

good luck

(1) motor oil only smells when its being burned.
(2) the output of the air ducts is in front of the gear shift area.
So, I'm thinking that you have an oil leak in the engine compartment (which may be dripping onto the exhaust system), and the oil has found a hot part of the engine/exhaust, and the smell of heated oil is wafting through the cabin air filter into the passenger compartment through the air ducts in the middle of the dash to just above the gear shift area.
If my theory is correct, you should be able to re-route the burned oil odor by changing the setting of your air ducts by changing the setting from its current setting to a "defrost-type" setting, wherein air entering the passenger compartment comes from the ducts below the windshield, rather then entering through the openings at the center of the console.
Ultimately, your fix will be to locate and resolve the oil leak.

Here's your list of possible culprits for the 1997 Nissan Pathfinder

Priority Action Part Type Cause
1 Inspect - Valve Cover Gasket -- Valve Cover Gasket Leaking Oil.
2 Inspect - Oil Filler Cap -- Oil Filler Cap Damaged or Missing.
3 Inspect - PCV Valve -- Plugged or Damaged PCV Valve.
4 Inspect - Oil Pan Gasket -- Leaking Oil Pan Gasket.
5 Inspect - Head Gasket -- Leaking Head Gasket.
6 Inspect - Oil Pump - divided O-ring or Oil Pump Gasket

If the odor really is gear oil (aka transmission fluid) and not motor oil, then there's a leak coming from the automatic transmission/manual transaxle.
Look under the transmission after the car has been parked awhile, and look for a reddish oil spot/blot/pool. transmission fluid is dyed red just for the purpose of differentiation from other automotive lubricants. You can assist the process of color differentiation by putting newspaper under the vehicle once it's been parked for the night.
Placing enough newspaper may also keep your Pathfinder from depositing a nearly-impossible-to-remove oil stain onto your garage floor overnight.
If you already have an oil stain on the floor, try a spray can of engine degreaser first. Citrus degreaser next.

sounds like tranny bad read codes first

check the transmission oil hot and with engine running in park
if ok you may have a bad transmission have it checked by a transmission shop sounds like bad silonoids inside

For 4W Hi either be stopped or moving at a slow rate of speed (<20 MPH) and move your 4WD selector to the 4 Wheel Hi position.

For 4W Lo stop and move the selector from 2W Hi to 4W Hi then push down on the selector and move through N into 4W Lo.

For 4W Hi either be stopped or moving at a slow rate of speed (<20 MPH) and move your 4WD selector to the 4 Wheel Hi position.

For 4W Lo stop and move the selector from 2W Hi to 4W Hi then push down on the selector and move through N into 4W Lo.